A 47-year-old man presents to the emergency room with 3 days of abdominal pain. The pain is localized in the left lower quadrant and suprapubic area. He has a low-grade fever (100.5°F), decreased appetite, and diarrhea. His pain has progressively worsened over the past few days, and today he is having discomfort with walking and getting out of bed. He has no previous history of similar episodes.
On physical examination, he is an obese man in mild distress. He has a temperature of 100.5°F and heart rate of 100 beats per minute. He has left lower quadrant tenderness on examination with focal peritoneal signs. He has leukocytosis of 17.5 with 85% neutrophils.
Diverticulosis, an outpouching in the colon, was first described in the 19th century and was considered to be a rare incidental finding. However, with an increased average population age and adoption of the Western diet in industrialized nations, rates of diverticulosis were noted to skyrocket to an estimated >80% by the age of 80 in the United States over past 30 years.1 Diverticulosis remains an asymptomatic condition, usually noted incidentally on imaging or colonoscopy. Only a small proportion of patients with diverticulosis will develop a problem—either diverticular bleeding or diverticulitis.
Although hard to estimate, approximately 10% to 20% of patients with diverticulosis will develop symptoms of diverticulitis. Of these patients, only 10% to 20% will be hospitalized, and less than half of hospitalized patients will require surgical intervention. This translates into roughly 1% of patients with diverticulosis who will need surgical resection.2
Diverticulitis can present in all age groups, but is most common in older patients (although in the Western world there has been a trend toward a younger age at presentation). Although younger patients tend to have higher rates of complicated diverticulitis and need for surgery, recent studies indicate that this is likely a function of age, rather than a different aspect of the disease. Men and women are affected equally, but men tend to present at a younger age and women tend to have a more fistulizing disease.
Diet is considered to be extremely important in the development of the disease, with a lifelong high-fiber diet being protective and a Western, low-fiber diet a risk factor. This is evident by increased rates of the diverticular disease in the population adapting a Western diet, as well as comparative studies between Western and Mediterranean type diets. There is no evidence, however, that adopting a high-fiber diet after development of diverticulosis (or a first attack of diverticulitis) decreases the chance of further diverticulitis. The use of opiates, nonsteroidal anti-inflammatory drugs (NSAIDs), cigarettes, and alcohol has also been proposed as risk factors; however, the data for this is not conclusive. Immunosuppression, meanwhile, is a very significant risk factor, correlated with higher rates of complicated disease, perforation, surgical ...